# Stem Leaf

Read a distribution while retaining raw values.

Canonical: https://chart.syidax.com/docs/components/stem-leaf/

<a id="overview"></a>

## sy-stem-leaf-chart

Inspect the digit distribution of a small numeric sample.

Choose the digit split and rounding unit first. Use Histogram for very large samples.

Base chart tier: Community. Features such as additional renderers and custom branding have separate entitlement requirements.

| Input | Data description |
| --- | --- |
| `values` | An array of raw numeric samples, displayed as stems and leaves. |

- [Run in Components](https://chart.syidax.com/charts/stem-leaf) — Change options and view framework-specific code
- [Shared installation and integration](https://chart.syidax.com/docs/getting-started.md)

<a id="example"></a>

## Complete implementation example

```html
<div id="chart-container" style="width: 100%; min-width: 0;"></div>

<script type="module">
  import { defineCustomElement as define0 } from '@syidax/advanced/components/sy-stem-leaf-chart.js';
  define0();

  const specs = [
    {
      "id": "example-chart",
      "tag": "sy-stem-leaf-chart",
      "props": {
        "engine": "standard",
        "values": [23, 25, 28, 29, 30, 31, 31, 32, 32, 33, 34, 34, 35, 35, 36, 37, 38, 39, 42, 45, 48, 52],
        "width": 640,
        "height": 360,
        "brandPosition": "bottom-right",
        "brandLogo": ""
      }
    }
  ];
  const container = document.querySelector('#chart-container');
  const elements = specs.map(({ tag, id, props }) => {
    const element = document.createElement(tag);
    element.id = id;
    Object.assign(element, props);
    element.setAttribute('aria-label', 'stem-leaf example chart');
    return element;
  });
  container.replaceChildren(...elements);
  const chart = elements.at(-1);
  const onEvent = event => {
    console.log('pointClick', event.detail);
  };
  chart.addEventListener('pointClick', onEvent);
  const observer = new ResizeObserver(([entry]) => {
    const width = Math.max(160, Math.floor(entry.contentRect.width));
    elements.forEach(element => { element.width = width; });
  });
  observer.observe(container);

  // In an SPA, call this function when the view is disposed.
  function disposeChart() {
    observer.disconnect();
    chart.removeEventListener('pointClick', onEvent);
    container.replaceChildren();
  }
</script>
```

<a id="props"></a>

## Properties

<a id="property-values"></a>

### values

An array of raw numeric samples, displayed as stems and leaves.

| Item | Value |
| --- | --- |
| JavaScript property | `values` |
| HTML attribute | Pass objects, arrays, and callbacks as JavaScript properties |
| Type | `StemLeafValues` |
| Default | `[]` |

- [StemLeafValues](https://chart.syidax.com/docs/types/StemLeafValues.md) — Type definition

<a id="property-width"></a>

### width

Chart width in pixels. If the container width changes, update width from a ResizeObserver.

| Item | Value |
| --- | --- |
| JavaScript property | `width` |
| HTML attribute | `width` |
| Type | `number` |
| Default | `520` |

<a id="property-height"></a>

### height

Chart height in pixels. Allow space for axes, titles, and the legend.

| Item | Value |
| --- | --- |
| JavaScript property | `height` |
| HTML attribute | `height` |
| Type | `number` |
| Default | `400` |

<a id="property-brandLogo"></a>

### brandLogo

The default is the Syidax symbol and wordmark. With the Pro chart.branding entitlement, set none to remove it or provide a PNG, JPEG, or WebP data URL to replace it.

| Item | Value |
| --- | --- |
| JavaScript property | `brandLogo` |
| HTML attribute | `brand-logo` |
| Type | `string` |
| Default | `undefined` |

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

<a id="property-brandPosition"></a>

### brandPosition

The corner where the logo is anchored. Community and Pro both support all four corners, using the same position on screen and in image exports.

| Item | Value |
| --- | --- |
| JavaScript property | `brandPosition` |
| HTML attribute | `brand-position` |
| Type | `'top-left' \| 'top-right' \| 'bottom-left' \| 'bottom-right'` |
| Default | `'bottom-right'` |
| Allowed values | `top-left`, `top-right`, `bottom-left`, `bottom-right` |

<a id="property-unit"></a>

### unit

Stem unit — one stem spans this much (default 10: stems are the tens digit).

| Item | Value |
| --- | --- |
| JavaScript property | `unit` |
| HTML attribute | `unit` |
| Type | `number` |
| Default | `10` |

<a id="property-split"></a>

### split

1 (default) or 2: each stem splits into 0–4 / 5–9 half-rows.

| Item | Value |
| --- | --- |
| JavaScript property | `split` |
| HTML attribute | `split` |
| Type | `1 \| 2` |
| Default | `1` |

<a id="property-color"></a>

### color

Ink colour (single CSS colour / array / comma string — first colour wins).

| Item | Value |
| --- | --- |
| JavaScript property | `color` |
| HTML attribute | Pass objects, arrays, and callbacks as JavaScript properties |
| Type | `string \| ReadonlyArray<string>` |
| Default | `'#111827'` |

<a id="property-activeColor"></a>

### activeColor

Accent for the hovered/focused leaf.

| Item | Value |
| --- | --- |
| JavaScript property | `activeColor` |
| HTML attribute | `active-color` |
| Type | `string` |
| Default | `'#2563eb'` |

<a id="property-showKey"></a>

### showKey

Show the reading key (`2 | 3 = 23`) under the plot.

| Item | Value |
| --- | --- |
| JavaScript property | `showKey` |
| HTML attribute | `show-key` |
| Type | `boolean` |
| Default | `true` |

<a id="property-chartTitle"></a>

### chartTitle

The title inside the chart. Explain the data's unit and meaning alongside it.

| Item | Value |
| --- | --- |
| JavaScript property | `chartTitle` |
| HTML attribute | `chart-title` |
| Type | `string` |
| Default | `undefined` |

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

<a id="property-chartSubtitle"></a>

### chartSubtitle

The subtitle inside the chart.

| Item | Value |
| --- | --- |
| JavaScript property | `chartSubtitle` |
| HTML attribute | `chart-subtitle` |
| Type | `string` |
| Default | `undefined` |

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

<a id="property-tooltipShow"></a>

### tooltipShow

Whether to display the built-in tooltip.

| Item | Value |
| --- | --- |
| JavaScript property | `tooltipShow` |
| HTML attribute | `tooltip-show` |
| Type | `boolean` |
| Default | `true` |

<a id="property-tooltipFormat"></a>

### tooltipFormat

Pass as a JavaScript property. type: (leaf: StemLeafPointEventDetail) => string.

| Item | Value |
| --- | --- |
| JavaScript property | `tooltipFormat` |
| HTML attribute | Pass objects, arrays, and callbacks as JavaScript properties |
| Type | `(leaf: StemLeafPointEventDetail) => string` |
| Default | `undefined` |

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

- [StemLeafPointEventDetail](https://chart.syidax.com/docs/types/StemLeafPointEventDetail.md) — Type definition

<a id="property-tooltip"></a>

### tooltip

Rich tooltip configuration object (family mirror). Property-only.

| Item | Value |
| --- | --- |
| JavaScript property | `tooltip` |
| HTML attribute | Pass objects, arrays, and callbacks as JavaScript properties |
| Type | `StemLeafTooltipInput` |
| Default | `undefined` |
| Literals in the type | `auto`, `off` |

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

- [StemLeafTooltipInput](https://chart.syidax.com/docs/types/StemLeafTooltipInput.md) — Type definition

<a id="property-enableMouseTracking"></a>

### enableMouseTracking

Set as an HTML attribute or JavaScript property. type: boolean.

| Item | Value |
| --- | --- |
| JavaScript property | `enableMouseTracking` |
| HTML attribute | `enable-mouse-tracking` |
| Type | `boolean` |
| Default | `true` |

<a id="property-zoom"></a>

### zoom

Zoom (Storybook parity, 2026-09-10) — the shared zoom surface as a VIEWPORT zoom: the plot area of the stems and leaves (the chart box minus the title band, the margins and the key band) is the plot, x 0 → 1 left to right and y 0 → 1 bottom to top. `'x'` | `'y'` | `'xy'` | `true` (x) enable the drag rectangle, the pan, Ctrl + wheel, the pinch and the keyboard (`+` / `-` / `Escape`); an object refines the switches. Off by default; `zoomTo` / `zoomBy` / `panBy` / `resetZoom` work regardless.

| Item | Value |
| --- | --- |
| JavaScript property | `zoom` |
| HTML attribute | Pass objects, arrays, and callbacks as JavaScript properties |
| Type | `CartesianZoomInput` |
| Default | `undefined` |
| Literals in the type | `auto`, `off`, `true`, `false`, `x`, `y`, `xy`, `inside` |

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

- [CartesianZoomInput](https://chart.syidax.com/docs/types/CartesianZoomInput.md) — Type definition

<a id="property-engine"></a>

### engine

Renderer selection: auto, standard, or pro. Engine selection is separate from permission to use a Pro chart type.

| Item | Value |
| --- | --- |
| JavaScript property | `engine` |
| HTML attribute | `engine` |
| Type | `StemLeafEngineMode` |
| Default | `'auto'` |
| Allowed values | `auto`, `standard`, `pro` |

- [StemLeafEngineMode](https://chart.syidax.com/docs/types/StemLeafEngineMode.md) — Type definition

<a id="property-unavailable"></a>

### unavailable

Allowed values: fallback, error, throw. Default: 'fallback'.

| Item | Value |
| --- | --- |
| JavaScript property | `unavailable` |
| HTML attribute | `unavailable` |
| Type | `StemLeafUnavailableBehaviour` |
| Default | `'fallback'` |
| Allowed values | `fallback`, `error`, `throw` |

- [StemLeafUnavailableBehaviour](https://chart.syidax.com/docs/types/StemLeafUnavailableBehaviour.md) — Type definition

<a id="property-streamSource"></a>

### streamSource

A stream source for live data. Check the contract for the specific type.

| Item | Value |
| --- | --- |
| JavaScript property | `streamSource` |
| HTML attribute | Pass objects, arrays, and callbacks as JavaScript properties |
| Type | `StemLeafStreamSource` |
| Default | `undefined` |

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

- [StemLeafStreamSource](https://chart.syidax.com/docs/types/StemLeafStreamSource.md) — Type definition

<a id="property-streamWindow"></a>

### streamWindow

The streaming data range to keep visible.

| Item | Value |
| --- | --- |
| JavaScript property | `streamWindow` |
| HTML attribute | `stream-window` |
| Type | `number` |
| Default | `undefined` |

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

<a id="property-streamMax"></a>

### streamMax

The maximum number of streaming data points to retain.

| Item | Value |
| --- | --- |
| JavaScript property | `streamMax` |
| HTML attribute | `stream-max` |
| Type | `number` |
| Default | `undefined` |

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

<a id="property-animated"></a>

### animated

Whether to animate initial display and data changes.

| Item | Value |
| --- | --- |
| JavaScript property | `animated` |
| HTML attribute | `animate` |
| Type | `boolean` |
| Default | `false` |

<a id="property-animationDuration"></a>

### animationDuration

Animation duration in milliseconds.

| Item | Value |
| --- | --- |
| JavaScript property | `animationDuration` |
| HTML attribute | `animation-duration` |
| Type | `number` |
| Default | `600` |

<a id="property-animationEasing"></a>

### animationEasing

Allowed values: linear, ease-out, ease-in, ease-in-out. Default: 'ease-out'.

| Item | Value |
| --- | --- |
| JavaScript property | `animationEasing` |
| HTML attribute | `animation-easing` |
| Type | `StemLeafEasing` |
| Default | `'ease-out'` |
| Allowed values | `linear`, `ease-out`, `ease-in`, `ease-in-out` |

- [StemLeafEasing](https://chart.syidax.com/docs/types/StemLeafEasing.md) — Type definition

<a id="property-animationType"></a>

### animationType

Allowed values: initial, update. Default: undefined.

| Item | Value |
| --- | --- |
| JavaScript property | `animationType` |
| HTML attribute | `animation-type` |
| Type | `StemLeafAnimationType` |
| Default | `undefined` |
| Allowed values | `initial`, `update` |

undefined means this property was not explicitly set. The effective value may depend on the chart type and other settings.

- [StemLeafAnimationType](https://chart.syidax.com/docs/types/StemLeafAnimationType.md) — Type definition

<a id="events"></a>

## Events

<a id="event-rendered"></a>

### rendered

Emits rendering results in detail when chart drawing completes.

Event name: `rendered`. Names are case-sensitive. Read the payload from `detail` on `CustomEvent<StemLeafRenderResult & { tier: StemLeafEngineTier }>`.

```javascript
chart.addEventListener('rendered', event => {
  console.log(event.detail); // StemLeafRenderResult & { tier: StemLeafEngineTier }
});
```

- [StemLeafRenderResult](https://chart.syidax.com/docs/types/StemLeafRenderResult.md) — Type definition
- [StemLeafEngineTier](https://chart.syidax.com/docs/types/StemLeafEngineTier.md) — Type definition

<a id="event-pointClick"></a>

### pointClick

A point selection event. Read the selected data and index from CustomEvent.detail.

Event name: `pointClick`. Names are case-sensitive. Read the payload from `detail` on `CustomEvent<StemLeafPointEventDetail>`.

```javascript
chart.addEventListener('pointClick', event => {
  console.log(event.detail); // StemLeafPointEventDetail
});
```

- [StemLeafPointEventDetail](https://chart.syidax.com/docs/types/StemLeafPointEventDetail.md) — Type definition

<a id="event-pointHover"></a>

### pointHover

CustomEvent.detail type: StemLeafPointEventDetail | null. Event names are case-sensitive.

Event name: `pointHover`. Names are case-sensitive. Read the payload from `detail` on `CustomEvent<StemLeafPointEventDetail | null>`.

```javascript
chart.addEventListener('pointHover', event => {
  console.log(event.detail); // StemLeafPointEventDetail | null
});
```

- [StemLeafPointEventDetail](https://chart.syidax.com/docs/types/StemLeafPointEventDetail.md) — Type definition

<a id="event-pointContextMenu"></a>

### pointContextMenu

CustomEvent.detail type: ChartPointContextMenuEventDetail<StemLeafPointEventDetail>. Event names are case-sensitive.

Event name: `pointContextMenu`. Names are case-sensitive. Read the payload from `detail` on `CustomEvent<ChartPointContextMenuEventDetail<StemLeafPointEventDetail>>`.

```javascript
chart.addEventListener('pointContextMenu', event => {
  console.log(event.detail); // ChartPointContextMenuEventDetail<StemLeafPointEventDetail>
});
```

- [ChartPointContextMenuEventDetail](https://chart.syidax.com/docs/types/ChartPointContextMenuEventDetail.md) — Type definition
- [StemLeafPointEventDetail](https://chart.syidax.com/docs/types/StemLeafPointEventDetail.md) — Type definition

<a id="event-appended"></a>

### appended

CustomEvent.detail type: { count: number }. Event names are case-sensitive.

Event name: `appended`. Names are case-sensitive. Read the payload from `detail` on `CustomEvent<{ count: number }>`.

```javascript
chart.addEventListener('appended', event => {
  console.log(event.detail); // { count: number }
});
```

<a id="event-windowSlid"></a>

### windowSlid

CustomEvent.detail type: { dropped: number }. Event names are case-sensitive.

Event name: `windowSlid`. Names are case-sensitive. Read the payload from `detail` on `CustomEvent<{ dropped: number }>`.

```javascript
chart.addEventListener('windowSlid', event => {
  console.log(event.detail); // { dropped: number }
});
```

<a id="event-chartAnimationStart"></a>

### chartAnimationStart

CustomEvent.detail type: void. Event names are case-sensitive.

Event name: `chartAnimationStart`. Names are case-sensitive. Read the payload from `detail` on `CustomEvent<void>`.

```javascript
chart.addEventListener('chartAnimationStart', event => {
  console.log(event.detail); // void
});
```

<a id="event-chartAnimationEnd"></a>

### chartAnimationEnd

CustomEvent.detail type: void. Event names are case-sensitive.

Event name: `chartAnimationEnd`. Names are case-sensitive. Read the payload from `detail` on `CustomEvent<void>`.

```javascript
chart.addEventListener('chartAnimationEnd', event => {
  console.log(event.detail); // void
});
```

<a id="event-chartAnimationInterrupted"></a>

### chartAnimationInterrupted

CustomEvent.detail type: void. Event names are case-sensitive.

Event name: `chartAnimationInterrupted`. Names are case-sensitive. Read the payload from `detail` on `CustomEvent<void>`.

```javascript
chart.addEventListener('chartAnimationInterrupted', event => {
  console.log(event.detail); // void
});
```

<a id="event-tooltipShow"></a>

### tooltipShow

Whether to display the built-in tooltip.

Event name: `tooltipShow`. Names are case-sensitive. Read the payload from `detail` on `CustomEvent<StemLeafTooltipShowEventDetail>`.

```javascript
chart.addEventListener('tooltipShow', event => {
  console.log(event.detail); // StemLeafTooltipShowEventDetail
});
```

- [StemLeafTooltipShowEventDetail](https://chart.syidax.com/docs/types/StemLeafTooltipShowEventDetail.md) — Type definition

<a id="event-tooltipHide"></a>

### tooltipHide

CustomEvent.detail type: void. Event names are case-sensitive.

Event name: `tooltipHide`. Names are case-sensitive. Read the payload from `detail` on `CustomEvent<void>`.

```javascript
chart.addEventListener('tooltipHide', event => {
  console.log(event.detail); // void
});
```

<a id="event-tooltipAction"></a>

### tooltipAction

CustomEvent.detail type: StemLeafTooltipActionEventDetail. Event names are case-sensitive.

Event name: `tooltipAction`. Names are case-sensitive. Read the payload from `detail` on `CustomEvent<StemLeafTooltipActionEventDetail>`.

```javascript
chart.addEventListener('tooltipAction', event => {
  console.log(event.detail); // StemLeafTooltipActionEventDetail
});
```

- [StemLeafTooltipActionEventDetail](https://chart.syidax.com/docs/types/StemLeafTooltipActionEventDetail.md) — Type definition

<a id="event-zoomChange"></a>

### zoomChange

Fired after every zoom change (drag / pan / wheel / pinch / keyboard / api / reset) with the new viewport windows.

Event name: `zoomChange`. Names are case-sensitive. Read the payload from `detail` on `CustomEvent<CartesianZoomChangeEventDetail>`.

```javascript
chart.addEventListener('zoomChange', event => {
  console.log(event.detail); // CartesianZoomChangeEventDetail
});
```

- [CartesianZoomChangeEventDetail](https://chart.syidax.com/docs/types/CartesianZoomChangeEventDetail.md) — Type definition

<a id="methods"></a>

## Methods

<a id="method-redraw"></a>

### redraw

Redraw the chart using its current data and options. Inspect the rendered result after the returned Promise resolves.

```typescript
redraw(): Promise<StemLeafRenderResult>
```

Return type: `Promise<StemLeafRenderResult>`. Call the method after element registration and await its Promise result.

- [StemLeafRenderResult](https://chart.syidax.com/docs/types/StemLeafRenderResult.md) — Type definition

<a id="method-getActiveTier"></a>

### getActiveTier

An asynchronous method. Check the argument and return types below.

```typescript
getActiveTier(): Promise<StemLeafEngineTier>
```

Return type: `Promise<StemLeafEngineTier>`. Call the method after element registration and await its Promise result.

- [StemLeafEngineTier](https://chart.syidax.com/docs/types/StemLeafEngineTier.md) — Type definition

<a id="method-setData"></a>

### setData

Replace the bar set.

```typescript
setData(values: StemLeafValues): Promise<void>
```

| Arguments | Type | Required |
| --- | --- | --- |
| `values` | `StemLeafValues` | Required |

Return type: `Promise<void>`. Call the method after element registration and await its Promise result.

- [StemLeafValues](https://chart.syidax.com/docs/types/StemLeafValues.md) — Type definition

<a id="method-appendPoint"></a>

### appendPoint

Append one value to the stream. Check the argument type and the licensing requirements for streaming.

```typescript
appendPoint(value: number): Promise<void>
```

| Arguments | Type | Required |
| --- | --- | --- |
| `value` | `number` | Required |

Return type: `Promise<void>`. Call the method after element registration and await its Promise result.

<a id="method-appendBatch"></a>

### appendBatch

Append multiple values to the stream. Check the argument type and the licensing requirements for streaming.

```typescript
appendBatch(values: ReadonlyArray<number>): Promise<void>
```

| Arguments | Type | Required |
| --- | --- | --- |
| `values` | `ReadonlyArray<number>` | Required |

Return type: `Promise<void>`. Call the method after element registration and await its Promise result.

<a id="method-shift"></a>

### shift

Drop the oldest streamed categories (the `data` boxes are not the stream).

```typescript
shift(count?: number): Promise<void>
```

| Arguments | Type | Required |
| --- | --- | --- |
| `count` | `number` | Optional |

Return type: `Promise<void>`. Call the method after element registration and await its Promise result.

<a id="method-replace"></a>

### replace

Swap the streamed set (`replace([])` clears it); the base `values` never leave. Without `chart.streaming` the dies upsert into the base like a batch (quietly: no `appended`, no `binChanged`, as a ring replace).

```typescript
replace(values: ReadonlyArray<number>): Promise<void>
```

| Arguments | Type | Required |
| --- | --- | --- |
| `values` | `ReadonlyArray<number>` | Required |

Return type: `Promise<void>`. Call the method after element registration and await its Promise result.

<a id="method-getStreamSource"></a>

### getStreamSource

The stream session's source (Chart Pro): like the stream methods it waits for a license still being confirmed.

```typescript
getStreamSource(): Promise<StemLeafStreamSource | undefined>
```

Return type: `Promise<StemLeafStreamSource | undefined>`. Call the method after element registration and await its Promise result.

- [StemLeafStreamSource](https://chart.syidax.com/docs/types/StemLeafStreamSource.md) — Type definition

<a id="method-setAnimation"></a>

### setAnimation

An asynchronous method. Check the argument and return types below.

```typescript
setAnimation(options: { duration?: number; easing?: StemLeafEasing; enabled?: boolean; type?: StemLeafAnimationType }): Promise<void>
```

| Arguments | Type | Required |
| --- | --- | --- |
| `options` | `{ duration?: number; easing?: StemLeafEasing; enabled?: boolean; type?: StemLeafAnimationType }` | Required |

Return type: `Promise<void>`. Call the method after element registration and await its Promise result.

- [StemLeafEasing](https://chart.syidax.com/docs/types/StemLeafEasing.md) — Type definition
- [StemLeafAnimationType](https://chart.syidax.com/docs/types/StemLeafAnimationType.md) — Type definition

<a id="method-pauseAnimation"></a>

### pauseAnimation

Pause the current animation.

```typescript
pauseAnimation(): Promise<void>
```

Return type: `Promise<void>`. Call the method after element registration and await its Promise result.

<a id="method-resumeAnimation"></a>

### resumeAnimation

Resume a paused animation.

```typescript
resumeAnimation(): Promise<void>
```

Return type: `Promise<void>`. Call the method after element registration and await its Promise result.

<a id="method-replayAnimation"></a>

### replayAnimation

Replay the initial sweep from min → value(s). No-op when animation is off / reduced.

```typescript
replayAnimation(): Promise<void>
```

Return type: `Promise<void>`. Call the method after element registration and await its Promise result.

<a id="method-hitTestLeaf"></a>

### hitTestLeaf

Stem-leaf-only — hit-test the leaf at canvas-relative coordinates.

```typescript
hitTestLeaf(cssX: number, cssY: number): Promise<{ sourceIndex: number; value: number; stemLabel: string; digit: number } | null>
```

| Arguments | Type | Required |
| --- | --- | --- |
| `cssX` | `number` | Required |
| `cssY` | `number` | Required |

Return type: `Promise<{ sourceIndex: number; value: number; stemLabel: string; digit: number } | null>`. Call the method after element registration and await its Promise result.

<a id="method-showTooltipAtLeaf"></a>

### showTooltipAtLeaf

Stem-leaf-only — programmatic tooltip open on a leaf by source index.

```typescript
showTooltipAtLeaf(sourceIndex: number): Promise<StemLeafPointEventDetail | null>
```

| Arguments | Type | Required |
| --- | --- | --- |
| `sourceIndex` | `number` | Required |

Return type: `Promise<StemLeafPointEventDetail | null>`. Call the method after element registration and await its Promise result.

- [StemLeafPointEventDetail](https://chart.syidax.com/docs/types/StemLeafPointEventDetail.md) — Type definition

<a id="method-hideTooltip"></a>

### hideTooltip

Close the currently visible tooltip.

```typescript
hideTooltip(): Promise<void>
```

Return type: `Promise<void>`. Call the method after element registration and await its Promise result.

<a id="method-zoomTo"></a>

### zoomTo

Zoom to explicit viewport windows: `x` / `y` as `{ min, max }` or `[min, max]` over 0..1 (`null` clears that orientation).

```typescript
zoomTo(request: CartesianZoomRequest): Promise<CartesianZoomChangeEventDetail | null>
```

| Arguments | Type | Required |
| --- | --- | --- |
| `request` | `CartesianZoomRequest` | Required |

Return type: `Promise<CartesianZoomChangeEventDetail | null>`. Call the method after element registration and await its Promise result.

- [CartesianZoomChangeEventDetail](https://chart.syidax.com/docs/types/CartesianZoomChangeEventDetail.md) — Type definition
- [CartesianZoomRequest](https://chart.syidax.com/docs/types/CartesianZoomRequest.md) — Type definition

<a id="method-zoomBy"></a>

### zoomBy

Scale the current windows by `factor` (< 1 zooms in) around `anchorFraction` (0..1, default centre).

```typescript
zoomBy(factor: number, anchorFraction?: number): Promise<CartesianZoomChangeEventDetail | null>
```

| Arguments | Type | Required |
| --- | --- | --- |
| `factor` | `number` | Required |
| `anchorFraction` | `number` | Optional |

Return type: `Promise<CartesianZoomChangeEventDetail | null>`. Call the method after element registration and await its Promise result.

- [CartesianZoomChangeEventDetail](https://chart.syidax.com/docs/types/CartesianZoomChangeEventDetail.md) — Type definition

<a id="method-panBy"></a>

### panBy

Slide the zoomed windows by viewport units (`{ x?, y? }`, 1 = the whole plot); a no-op at the full extent.

```typescript
panBy(delta: { x?: number; y?: number }): Promise<CartesianZoomChangeEventDetail | null>
```

| Arguments | Type | Required |
| --- | --- | --- |
| `delta` | `{ x?: number; y?: number }` | Required |

Return type: `Promise<CartesianZoomChangeEventDetail | null>`. Call the method after element registration and await its Promise result.

- [CartesianZoomChangeEventDetail](https://chart.syidax.com/docs/types/CartesianZoomChangeEventDetail.md) — Type definition

<a id="method-resetZoom"></a>

### resetZoom

Reset the zoomed or panned range to the original data range.

```typescript
resetZoom(): Promise<CartesianZoomChangeEventDetail | null>
```

Return type: `Promise<CartesianZoomChangeEventDetail | null>`. Call the method after element registration and await its Promise result.

- [CartesianZoomChangeEventDetail](https://chart.syidax.com/docs/types/CartesianZoomChangeEventDetail.md) — Type definition

<a id="method-getZoom"></a>

### getZoom

Read the current zoom range. Check the return type's nullability and the range for each axis.

```typescript
getZoom(): Promise<CartesianZoomState | null>
```

Return type: `Promise<CartesianZoomState | null>`. Call the method after element registration and await its Promise result.

- [CartesianZoomState](https://chart.syidax.com/docs/types/CartesianZoomState.md) — Type definition

<a id="method-getZoomExtent"></a>

### getZoomExtent

The full extent (0..1 on both orientations, key `'0'`).

```typescript
getZoomExtent(request?: CartesianZoomExtentRequest): Promise<CartesianZoomExtentDetail | null>
```

| Arguments | Type | Required |
| --- | --- | --- |
| `request` | `CartesianZoomExtentRequest` | Optional |

Return type: `Promise<CartesianZoomExtentDetail | null>`. Call the method after element registration and await its Promise result.

- [CartesianZoomExtentDetail](https://chart.syidax.com/docs/types/CartesianZoomExtentDetail.md) — Type definition
- [CartesianZoomExtentRequest](https://chart.syidax.com/docs/types/CartesianZoomExtentRequest.md) — Type definition

<a id="method-getEngineStatus"></a>

### getEngineStatus

Requested engine vs what runs, and why (CHART-ADD-08): always Standard (this type has no WebGPU renderer); read without side effects, never consults the license.

```typescript
getEngineStatus(): Promise<ChartEngineStatus>
```

Return type: `Promise<ChartEngineStatus>`. Call the method after element registration and await its Promise result.

- [ChartEngineStatus](https://chart.syidax.com/docs/types/ChartEngineStatus.md) — Type definition